Safety switch



H. C. PIERSON I SAFETY SWITCH 4 Sept. 3, 1935.

Filed Nov. 16, 1955 Inventor C Pierson flllomey Patented Sept. 3, 1935UNITED STATES PATENT OFFICE third to Reginald Wayne Lockiin, RiverJunction, Fla and one-third to Henry Earl Pierson, Quincy Fla.

Application November 16, 1933, Serial No. 698,833

lclaim.

' 'This invention relates to safety switches of the kind used onautomobiles for automatically interrupting the ignition circuit in theevent the automobile is turned over and thereby eliminate the dangerofinJury by fire.

The object of the invention is to provide a switch of this character forgrounding the ignition circuit upon the happening of the abovecontingency; and further to simplify the construction of, and rendermore positive the operation of such safety devices.

In the drawing:

Figure l is an elevational view of the switch.

Figure 2 is a sectional view therethrough.

Figure 3 is a horizontal section taken on line 3-4 of Figure 2.-Figure4isaviewoftheswitchinaninclined or canted position, with partsbroken away to illustrate the operation and Figure 5 is a wiringdiagram.

Referring to the drawing by numerals the invention, in the illustratedembodiment thereof. comprises a substantially sealed casing ll ofconductive material, having a cap ll, of di-electric material secured onthe top thereof by suitable fastening elements It.

A metallic socket II is embedded centrally within the cap II, and has aretaining flange ll integral therewith to firmly secure the socket.

A pendulum i5 is provided with a ball-head l6 engaged in the socket asshown to suspend the pendulum in the casing for universal movement.Integral with socket It is a binding post ll that projects through thetop of the cap and to which the wire it is secured by the nut II in theconventional manner.

To protect the above electrical connection an elastic cap or sleeve 20is provided as shown clearly in Figure 2.

For mounting the device in a vertical position on a suitable part 2! ofthe automobile, as for example, the instrument board, vertically spacedbolts 22 are provided on the casing II.

In Figure 2 the device is shown mounted, and in Figure 5, B indicatesthe battery, 23 the ignition switch, it the wire leading from one sideof the switch to the coil 2!, while 2 indicates the distributor, all ofwhich is conventional and is embodied in automobile ignition systems.

Normally the pendulum I5 is perpendicular. Should however, as forexample, in the event of an accident, the automobile turn over, and theignition switch 23 is closed a grounding of the circuit willautomatically take place, since the pendulum will swing into engagementwith the wall of easing It as shown in Figure 4 thus grounding thecircuit, as is thought apparent. The circuit being grounded in thismanner the 5 motor will stop and the danger of fire thus overcome.

The frictional engagement between ball I and socket I! will be such asto restrain material swinging movement of the pendulum, as might l0otherwise result from vibration. Also the socket I3 is provided with aninternal conical formation 26, the point of which is slightly spacedfrom the ball l6 and slightly to one side of the vertical diameter ofthe ball. Thus if the vehicle 15 should turn completely upside down, theball, resting on this point, would rotate under the action of the weightl5 and thus the weight would strike the casing and thus ground thecircuit and the purpose of same is to guard against 20 the pendulumremaining vertical should the automobile turn completely up-side-down,and, under such circumstances to insure a swinging of the pendulumthrough an arc sufllcient to engage the wall of casing Ill for grounding5 the circuit.

Having thus described my invention, what I claim is:

A safety switch comprising a casing of conducting material having itsupper end open, a 30 cap closing the open end of the casing and formedof non-conducting material, a centrally arranged socket member havingits upper portion embedded in the cap with its upper end spaced from thetop surface of the cap, the 35 socketed part of the member dependinginto the casing, a ball fitting in the socket and the end wall of thesocket being pressed inwardly into engagement with the ball to hold theball in place and to prevent too free movement of the ball, a stemconnected with the ball and depending therefrom into the casing, aweight connected with the lower end of the stem, said weight engagin thecasing when the casing is tilted, a binding post connected with theupper end of 5 the socket member and passing through the upper surfaceof the cap, and a conical projection on the socket member and dependinginto the socket thereof and forming a pointed seat for the ball when thecasing is inverted whereby the ball will rotate and the weight willengage the casing.

HENRY C. PIERSON.

